I'll give it a stab:
Plugs and leads, Magnecore and NGK
Brake disks and pads, if you have 14s, do the big disk conversion, Marea (etc) calipers, stock pads, pattern Alfa 155 disks. Pratting around with the standard size disks and pads is a (relative) waste of money.
Springs -- I dunno -- I suspect they're all really made by one of the same 3 companies!
Strut brace -- the only one you're likely to get is OMP. They're horrible and you might have fitting problems with the ABS.
Air filter -- go GSR.